In the field of high-speed computers, high-density, high-speed electronic devices exhibit above-average power consumption characteristics. Such power consumption leads to extreme heat generation. A cooling apparatus must be able to efficiently dissipate heat from the electronic devices.
The co-pending and commonly assigned U.S. patent application Ser. No. 07/284,992, filed Dec. 14, 1988, by August et al., entitled "COOLING PLATE WITH INTERBOARD CONNECTOR APERTURES FOR CIRCUIT BOARD ASSEMBLIES", describes a cooling plate for heat dissipation that is particularly adapted for use with stacks of printed circuit boards. The cooling plate includes apertures and mounting means for Z-axis connector assemblies so that printed circuit boards attached to either side of the cooling plate may be electrically interconnected. Externally, the cooling plate has a fixed pattern of the heat conductive pads that are substantially identical to the pattern of devices on a printed circuit board attached to the cooling plate. The use of such fixed patterns prevent specific cooling plates from being used with more than one configuration of printed circuit board. Each printed circuit board has a different pattern of devices thereon, and thus requires a different cooling plate. In addition, careful manufacturing of the cooling plate and equally careful mounting of devices on the printed circuit board is required to ensure optimal heat dissipation.
The commonly assigned U.S. Pat. No. 4,628,407, issued Dec. 9, 1986, to August et al., entitled "CIRCUIT MODULE WITH ENHANCED HEAT TRANSFER AND DISTRIBUTION", describes a printed circuit board used in a high performance computer. A printed circuit board stack is disclosed which includes a heat-conducting plate situated therein. The printed circuit boards contain thermally conductive paths from each circuit device mounted thereon through the printed circuit board to locations in contact with the cooling plate. This system provides good heat dissipation properties, but tolerance variations in the thickness of the printed circuit board can affect the thickness of the thermal compound between the thermal connector and the circuit device.